ReactOS  0.4.15-dev-492-ga1108f6
md4.c
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1 /*
2  * Copyright (C) 2001 Nikos Mavroyanopoulos
3  * Copyright (C) 2004 Hans Leidekker
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with this library; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
18  */
19 
20 /*
21  * This code implements the MD4 message-digest algorithm.
22  * It is based on code in the public domain written by Colin
23  * Plumb in 1993. The algorithm is due to Ron Rivest.
24  *
25  * Equivalent code is available from RSA Data Security, Inc.
26  * This code has been tested against that, and is equivalent,
27  * except that you don't need to include two pages of legalese
28  * with every copy.
29  *
30  * To compute the message digest of a chunk of bytes, declare an
31  * MD4_CTX structure, pass it to MD4Init, call MD4Update as
32  * needed on buffers full of bytes, and then call MD4Final, which
33  * will fill a supplied 16-byte array with the digest.
34  */
35 
36 #include "md4.h"
37 #include "util.h"
38 
39 static void MD4Transform( unsigned int buf[4], unsigned int const in[16] );
40 
41 /*
42  * Start MD4 accumulation. Set bit count to 0 and buffer to mysterious
43  * initialization constants.
44  */
46 {
47  ctx->buf[0] = 0x67452301;
48  ctx->buf[1] = 0xefcdab89;
49  ctx->buf[2] = 0x98badcfe;
50  ctx->buf[3] = 0x10325476;
51 
52  ctx->i[0] = ctx->i[1] = 0;
53 }
54 
55 /*
56  * Update context to reflect the concatenation of another buffer full
57  * of bytes.
58  */
59 VOID NTAPI MD4Update( MD4_CTX *ctx, const unsigned char *buf, unsigned int len )
60 {
61  register unsigned int t;
62 
63  /* Update bitcount */
64  t = ctx->i[0];
65 
66  if ((ctx->i[0] = t + (len << 3)) < t)
67  ctx->i[1]++; /* Carry from low to high */
68 
69  ctx->i[1] += len >> 29;
70  t = (t >> 3) & 0x3f;
71 
72  /* Handle any leading odd-sized chunks */
73  if (t)
74  {
75  unsigned char *p = (unsigned char *)ctx->in + t;
76  t = 64 - t;
77 
78  if (len < t)
79  {
80  memcpy( p, buf, len );
81  return;
82  }
83 
84  memcpy( p, buf, t );
85  byteReverse( ctx->in, 16 );
86 
87  MD4Transform( ctx->buf, (unsigned int *)ctx->in );
88 
89  buf += t;
90  len -= t;
91  }
92 
93  /* Process data in 64-byte chunks */
94  while (len >= 64)
95  {
96  memcpy( ctx->in, buf, 64 );
97  byteReverse( ctx->in, 16 );
98 
99  MD4Transform( ctx->buf, (unsigned int *)ctx->in );
100 
101  buf += 64;
102  len -= 64;
103  }
104 
105  /* Handle any remaining bytes of data. */
106  memcpy( ctx->in, buf, len );
107 }
108 
109 /*
110  * Final wrapup - pad to 64-byte boundary with the bit pattern
111  * 1 0* (64-bit count of bits processed, MSB-first)
112  */
114 {
115  unsigned int count;
116  unsigned char *p;
117 
118  /* Compute number of bytes mod 64 */
119  count = (ctx->i[0] >> 3) & 0x3F;
120 
121  /* Set the first char of padding to 0x80. This is safe since there is
122  always at least one byte free */
123  p = ctx->in + count;
124  *p++ = 0x80;
125 
126  /* Bytes of padding needed to make 64 bytes */
127  count = 64 - 1 - count;
128 
129  /* Pad out to 56 mod 64 */
130  if (count < 8)
131  {
132  /* Two lots of padding: Pad the first block to 64 bytes */
133  memset( p, 0, count );
134  byteReverse( ctx->in, 16 );
135  MD4Transform( ctx->buf, (unsigned int *)ctx->in );
136 
137  /* Now fill the next block with 56 bytes */
138  memset( ctx->in, 0, 56 );
139  }
140  else
141  {
142  /* Pad block to 56 bytes */
143  memset( p, 0, count - 8 );
144  }
145 
146  byteReverse( ctx->in, 14 );
147 
148  /* Append length in bits and transform */
149  ((unsigned int *)ctx->in)[14] = ctx->i[0];
150  ((unsigned int *)ctx->in)[15] = ctx->i[1];
151 
152  MD4Transform( ctx->buf, (unsigned int *)ctx->in );
153  byteReverse( (unsigned char *)ctx->buf, 4 );
154  memcpy( ctx->digest, ctx->buf, 16 );
155 }
156 
157 /* The three core functions */
158 
159 #define rotl32(x,n) (((x) << ((unsigned int)(n))) | ((x) >> (32 - (unsigned int)(n))))
160 
161 #define F( x, y, z ) (((x) & (y)) | ((~x) & (z)))
162 #define G( x, y, z ) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
163 #define H( x, y, z ) ((x) ^ (y) ^ (z))
164 
165 #define FF( a, b, c, d, x, s ) { \
166  (a) += F( (b), (c), (d) ) + (x); \
167  (a) = rotl32( (a), (s) ); \
168  }
169 #define GG( a, b, c, d, x, s ) { \
170  (a) += G( (b), (c), (d) ) + (x) + (unsigned int)0x5a827999; \
171  (a) = rotl32( (a), (s) ); \
172  }
173 #define HH( a, b, c, d, x, s ) { \
174  (a) += H( (b), (c), (d) ) + (x) + (unsigned int)0x6ed9eba1; \
175  (a) = rotl32( (a), (s) ); \
176  }
177 
178 /*
179  * The core of the MD4 algorithm
180  */
181 static void MD4Transform( unsigned int buf[4], const unsigned int in[16] )
182 {
183  register unsigned int a, b, c, d;
184 
185  a = buf[0];
186  b = buf[1];
187  c = buf[2];
188  d = buf[3];
189 
190  FF( a, b, c, d, in[0], 3 );
191  FF( d, a, b, c, in[1], 7 );
192  FF( c, d, a, b, in[2], 11 );
193  FF( b, c, d, a, in[3], 19 );
194  FF( a, b, c, d, in[4], 3 );
195  FF( d, a, b, c, in[5], 7 );
196  FF( c, d, a, b, in[6], 11 );
197  FF( b, c, d, a, in[7], 19 );
198  FF( a, b, c, d, in[8], 3 );
199  FF( d, a, b, c, in[9], 7 );
200  FF( c, d, a, b, in[10], 11 );
201  FF( b, c, d, a, in[11], 19 );
202  FF( a, b, c, d, in[12], 3 );
203  FF( d, a, b, c, in[13], 7 );
204  FF( c, d, a, b, in[14], 11 );
205  FF( b, c, d, a, in[15], 19 );
206 
207  GG( a, b, c, d, in[0], 3 );
208  GG( d, a, b, c, in[4], 5 );
209  GG( c, d, a, b, in[8], 9 );
210  GG( b, c, d, a, in[12], 13 );
211  GG( a, b, c, d, in[1], 3 );
212  GG( d, a, b, c, in[5], 5 );
213  GG( c, d, a, b, in[9], 9 );
214  GG( b, c, d, a, in[13], 13 );
215  GG( a, b, c, d, in[2], 3 );
216  GG( d, a, b, c, in[6], 5 );
217  GG( c, d, a, b, in[10], 9 );
218  GG( b, c, d, a, in[14], 13 );
219  GG( a, b, c, d, in[3], 3 );
220  GG( d, a, b, c, in[7], 5 );
221  GG( c, d, a, b, in[11], 9 );
222  GG( b, c, d, a, in[15], 13 );
223 
224  HH( a, b, c, d, in[0], 3 );
225  HH( d, a, b, c, in[8], 9 );
226  HH( c, d, a, b, in[4], 11 );
227  HH( b, c, d, a, in[12], 15 );
228  HH( a, b, c, d, in[2], 3 );
229  HH( d, a, b, c, in[10], 9 );
230  HH( c, d, a, b, in[6], 11 );
231  HH( b, c, d, a, in[14], 15 );
232  HH( a, b, c, d, in[1], 3 );
233  HH( d, a, b, c, in[9], 9 );
234  HH( c, d, a, b, in[5], 11 );
235  HH( b, c, d, a, in[13], 15 );
236  HH( a, b, c, d, in[3], 3 );
237  HH( d, a, b, c, in[11], 9 );
238  HH( c, d, a, b, in[7], 11 );
239  HH( b, c, d, a, in[15], 15 );
240 
241  buf[0] += a;
242  buf[1] += b;
243  buf[2] += c;
244  buf[3] += d;
245 }
246 
unsigned char digest[16]
Definition: util.c:86
VOID NTAPI MD4Final(MD4_CTX *ctx)
Definition: md4.c:113
static void MD4Transform(unsigned int buf[4], unsigned int const in[16])
Definition: md4.c:181
GLenum GLuint GLenum GLsizei const GLchar * buf
Definition: glext.h:7751
GLuint GLuint GLsizei count
Definition: gl.h:1545
GLdouble GLdouble t
Definition: gl.h:2047
#define HH(a, b, c, d, x, s)
Definition: md4.c:173
NTSTATUS(* NTAPI)(IN PFILE_FULL_EA_INFORMATION EaBuffer, IN ULONG EaLength, OUT PULONG ErrorOffset)
Definition: IoEaTest.cpp:117
#define a
Definition: ke_i.h:78
unsigned int buf[4]
Definition: util.c:83
void byteReverse(unsigned char *buf, unsigned longs)
Definition: util.c:8
unsigned int i[2]
Definition: util.c:84
#define b
Definition: ke_i.h:79
GLboolean GLboolean GLboolean b
Definition: glext.h:6204
#define d
Definition: ke_i.h:81
if(!(yy_init))
Definition: macro.lex.yy.c:714
const GLubyte * c
Definition: glext.h:8905
#define memcpy(s1, s2, n)
Definition: mkisofs.h:878
GLenum GLsizei len
Definition: glext.h:6722
#define GG(a, b, c, d, x, s)
Definition: md4.c:169
VOID NTAPI MD4Update(MD4_CTX *ctx, const unsigned char *buf, unsigned int len)
Definition: md4.c:59
unsigned char in[64]
Definition: util.c:85
Definition: util.c:81
GLuint in
Definition: glext.h:9616
#define FF(a, b, c, d, x, s)
Definition: md4.c:165
VOID NTAPI MD4Init(MD4_CTX *ctx)
Definition: md4.c:45
#define c
Definition: ke_i.h:80
GLboolean GLboolean GLboolean GLboolean a
Definition: glext.h:6204
GLfloat GLfloat p
Definition: glext.h:8902
#define memset(x, y, z)
Definition: compat.h:39